5.7 engine failure

New member looking for advice. I have a 2013 Tundra 5.7 with 115000 miles. Well taken care of up to date on all maintenance. Driving at 65 mph the engine started running very rough as if I was going over a rumble strip in the road.
Limped it to a Toyota dealer where they started with spark plug replacement. Diagnosed it as miss fire on 6 of the 8 cylinders. $500 No change. Next, replaced engine wire harness, $4500 No change. They recommend an engine replacement at $25000.
My truck is now at an independent shop awaiting a diagnosis from them.
The truck starts but seems to be running on 2 or 3 cylinders, very rough as expected, does at idle. Catastrophic engine failure? Cam shafts kaput? Anyone else have similar experience? Thoughts?

 

$25,000 for a new engine? WOW! I'd just go buy a new truck at that point.

I'm curious to see what the independent shops says.

 

Sounds like a blown head gasket on that bank. When was the coolant changed last?

if they would have borescoped it initially, it's likely they would have seen a steam cleaned cylinder or two. I'd want my $4,500 back for the harness you didn't need.

 

Coolant changed about a year ago, could understand it during winter months, this just happened a few weeks ago.

 

You could understand what during winter months? Was that coolant change a year ago the first and only coolant change? Did you drain the engine or just dump and refill the radiator? What coolant was used?

I know it's a lot of questions but this is somewhat of a hot topic for pre2014 tundras...

 

Wouldn’t there be coolant in the oil with a blown head gasket?

 

Drained and flushed the engine, I used recommend coolant for Toyota, orange stuff.

 

Not necessarily. Sounds like it's leaking into the cylinder. You probably have exhaust gases in your coolant - that would confirm a blown HG. As would inspecting the cylinder for shiny clean.

 

Ouch. No Toyota coolant is orange. Orange is for domestics. Pink or red for Toyotas.

what did you use to flush the engine?

 

$4500 for a harness you didn’t need is ridiculous. Sounds like they loaded the parts cannon for you.

Ready, aim, FIRE!

There goes your bank account. Get a remanufacture for 8K and find an independent shop to swap it out.

 

Thinking that the coolant was beyond its freeze protection capacity causing head damage or gasket failure during a low temperature event. Winter months

 

ummm, not sure where you are located, but there are a number of examples on this site of both salvage yard and remanufactured engines getting swapped in for ~$10k total. I'm not even close to $25k and I have a built long block and billet fuel rails included in my cost. You're doing the right thing to get other opinions. They obviously don't want to figure it out for you, or they are hoping you will sell it to them.

 

Most times when a head gasket fails - it's nothing to do with cold / freezing temps. That cracks blocks. Using incompatible coolant definitely can contribute to head gasket failure.

 

Yea, it’s like they priced it to rebuild a Turd- Gen short block.

 

Whoever sold him the harness is incompetent, a crook, or both.

 

In this context it was: Ready, FIRE!, aim. Or they skipped the last one altogether.

 

My mistake, pink! Drained the radiator, ran the engine to circulate then drain again.

 

Thanks all for the reply’s! Gives me some ideas moving forward. Will post up how it all comes out!

 

What dealership was it?

 

Durango Motor Co. Toyota dealership in Durango Colorado

 

@rocketdog

Sorry to hear you are having problems.

Check this video on head gasket fails on the UR engines.

https://youtu.be/dfGTI0sWozc?si=CljOsCmGxt2VEeAX

Although the cause of your issue isn't exactly known yet, I hope it works out in your best favor.

 

If initial diagnostics is correct with misfire 6 and 8 through codes ... I would start there

 

Call Yota corp line. Report what transpired and the cost.

 

Valley coolant leak?? What cylinders were impacted??

 

This whole mess is a horror story! First off, maybe suddenly just sucked in a plastic bag or similar and isn't getting air. Check for air flow. Then check for fuel pressure and overall fuel system. Lastly, check for fire. If all good, go on to boroscope plug bores, check compression, and test coolant for head gasket leaks. If all good there and runs like crap check for clogged catalytic converter. DO NOT just order an engine until a thourough checklist is done. You could just find a bad brain was the real problem after you swapped the engine. Also, grounds and battery terminals, be sure those are good!

 

It would be nice to have the details of their diagnostics that made them say the engine needs to be replaced if your only symptom is misfiring.

 

Any recent fuel ups? Might just be bad gas such as having water in it or the delivery driver put the hose into the wrong fuel port and you have diesel mixed in the tank.

 

I thinks it's obvious by now, but don't go back to that dealer. I'll also reiterate that there is now way that the cold had anything to do with any head gaskets failures.

 

Wow this is scary for somebody like myself who is interested in a 2nd gen truck. 115k miles? That's unfortunately the mileage where my budget allows, since these trucks seemingly are appreciating.